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1.
We consider the problem of nonparametric multi-product dynamic pricing with unknown demand and show that the problem may be formulated as an online model-free stochastic program, which can be solved by the classical Kiefer-Wolfowitz stochastic approximation (KWSA) algorithm. We prove that the expected cumulative regret of the KWSA algorithm is bounded above by where κ1, κ2 are positive constants and T is the number of periods for any T = 1, 2, … . Therefore, the regret of the KWSA algorithm grows in the order of , which achieves the lower bounds known for parametric dynamic pricing problems and shows that the nonparametric problems are not necessarily more difficult to solve than the parametric ones. Numerical experiments further demonstrate the effectiveness and efficiency of our proposed KW pricing policy by comparing with some pricing policies in the literature.  相似文献   
2.
对消防监督管理制度改革的思考   总被引:1,自引:1,他引:0  
由于多年来理论界和实务界对消防监督管理内涵认识不统一 ,使用较为混乱。而消防监督管理的内涵与对消防监督管理制度的认识直接相关 ,故对此进行了分析并给予界定。在此基础上对消防监督管理制度的发展、存在问题进行阐述分析 ,结合当前形势和消防监督管理的发展趋势提出了完善消防监督管理制度的改革思路。  相似文献   
3.
意境是中国古典美学中极具哲学思辨的审美范畴,是艺术的至境。它的生成与禅宗有着密切的关联。对意境的理解与阐释,必须将它与禅宗联在一起。意境与禅宗异质同构,殊途同归。  相似文献   
4.
《水浒传》的情节所体现出的作者的艺术造诣,一直为读者和批评家津津乐道。对于三个女人的情节,体现了现代文学理论的设计理念,值得我们重视。本文试从因果逻辑这一规律来考察这三个相似情节中的相异性,从中我们可以看出作者深厚的艺术功底。  相似文献   
5.
A truly universal ban on anti-personnel mines cannot be realized without engagement of armed non-state actors and armed groups operating outside state control, including rebels and national liberation movements. Events after 9/11 have complicated engagement with organizations that can be classified as ‘terrorists’. Yet, the use of anti-personnel landmines itself can be viewed as an act of terrorism and African leaders have, on various occasions, classified the use of landmines and the presence of unexploded ordnance as engendering insecurity and a serious impediment to development. The success of a total ban ultimately depends upon ensuring that armed non-state actors act in accordance with international humanitarian law. The Geneva Call Deed of Commitment for Adherence to a Total Ban on Anti-Personnel Mines and for Cooperation in Mine Action (DoC) might be described as an alternative instrument to the Anti-Personnel Mine Ban Convention and can serve an important and impartial channel of communication with non-state actors. Already 18 armed groups in Africa have signed the Geneva Call DoC.  相似文献   
6.
This article discusses the validity of national security threats in Botswana and whether they justified the creation of the Directorate of Intelligence and Security Services (DISS), which has been controversial since its formation. Since its inception in 2008, the DISS has been accused of many human rights violations and politicisation. Without fully deliberating on the basis for its creation, some discourses have focused on the politicised operations without relation to what the DISS is supposed to be doing. The author works under the assumption that debates should be shaped by whether it was necessary to create the DISS, and, if so, how we can shape and steer debates on its oversight, management, reform and operations. This article argues that despite the politicisation of the DISS, Botswana's national security threats are both real and imagined; and that domestic threats to national security have moved from the conceptual ‘imagined’ category to the ‘real’. However, that in itself did not warrant the design and mandate of the DISS, and the article argues that it was external threats that really warranted the creation of a civilian intelligence agency. The article concludes that Botswana faces a plethora of external security threats – traditional and non-traditional – that warranted the creation and continuance of the DISS.  相似文献   
7.
针对我军后方仓库弹药装卸运输环节对人员叉车操作的安全性需求,设计出了叉车操作测试场地路线,归纳总结了人员操作叉车进行弹药装卸运输环节中的安全失效形式及失效原因,构建了HRA评估数学模型.选取我军某后方仓库搬运机械建制班人员为对象,进行了实地测试,得到了弹药装卸运输环节的人为失误概率.测试结果表明,基于CREAM方法能够较好地解决后方仓库弹药装卸运输环节人为失误概率的量化问题.  相似文献   
8.
摘要:针对单小批量武器装备保障的特殊需求,对传统的质量屋模型进行了改进,建立了基于装备保障需求与保障规则的质量屋模型,利用整数规划技术进行求解,使得单小批量武器的装备保障规则按照实际保障需求重新排列优先次序,并通过对某型火炮保障方案的筛选验证了模型的正确性.新的质量屋模型发展完善了质量屋的理论与方法,有助于提高单小批量武器的装备保障能力.  相似文献   
9.
针对军队干部交流分配常常采用定性方法的现状,结合每年都要交流大量干部的实际情况,在可行、合理交流的基础上,综合利用Delphi法、系统分解与协调法建立了干部交流分配模型,从而实现了干部在各种类别之间的交流,为军队干部的交流分配提供了定量依据.  相似文献   
10.
We address infinite‐horizon models for oligopolies with competing retailers under demand uncertainty. We characterize the equilibrium behavior which arises under simple wholesale pricing schemes. More specifically, we consider a periodic review, infinite‐horizon model for a two‐echelon system with a single supplier servicing a network of competing retailers. In every period, each retailer faces a random demand volume, the distribution of which depends on his own retail price as well as those charged by possibly all competing retailers. We also derive various comparative statics results regarding the impact several exogenous system parameters (e.g., cost or distributional parameters) have on the equilibrium decisions of the retailers as well as their expected profits. We show that certain monotonicity properties, engrained in folklore as well as in known inventory models for centralized systems, may break down in decentralized chains under retailer competition. Our results can be used to optimize the aggregate profits in the supply chain (i.e., those of the supplier and all retailers) by implementing a specific wholesale pricing scheme. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004.  相似文献   
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